Question

A pontoon boat (weight 1200 lb) sits at rest on a still lake near a dock. Your friend, whose weight is 120 lb, runs off the end of the dock at a speed of 12 mi/hr and jumps onto the deck of the boat. She has not taken physics and is surprised to find that the boat ends up moving away from the dock. How fast is it moving just after she lands?

Answer 1

Using law of conservation of energy,

m u = m v

1200 x V = 120 x 12

Velocity, v = 120 x 12/1200 = 1.2 mi/hr

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